The Obrenovac First Elementary School is the first established school in Belgrade, almost 200 years old. During the two centuries pupils of this school had no adequate indoor space for physical education and sports activities.
From the very beginning the idea was to design low budget, energy efficient and sustainable building with no unnecessary details.
As Obrenovac Municipality is close to the river Sava banks, it is under the influence of the underground water. This was the crucial technical problem which had to be resolved from the first preliminary design phase. Through design process, the solution for these challenges has been successfully found by designing the waterproof concrete hull, 5 meters deep in the ground, just few centimeters over the highest underground water level. This concept provided some kind of waterproof box, as boat sink, for all premises inside.